Perforating machine and method

ABSTRACT

A method and machine for impressing a row of longitudinal perforations in a material such as a steel pipe. A female die engages one surface of the metal, and a cutter positioned on the other side cuts and forms the perforations as it is advanced longitudinally. The cutter has a rotatable head provided with a number of teeth that register with the die to cut and form the perforations as the cutter advances. The preferred embodiment includes ratchet means for shifting the material to a new position upon completion of a row of perforations.

United States Patent Darling [54] PERFORATING MACHINE AND METHOD [72] Inventor: Donald J. Darling, Hutchinson,

Kans.

[73] Assignee: Rosencrantz and Bernis Enterprises, Great Bend, Kans.

22] Filed: April 9, 1970 21 Appl.No.: 26,873

[52] US. Cl. ..72/204, 72/186, 72/219, 72/326 [51] Int. Cl. ..B2lh 1100 [58] Field of Search ..72/204, 71, 186, 325, 326, 72/327; 29/210, 163.5

[56] References Cited UNITED STATES PATENTS 1,785,071 12/1930 Coberly ..29/163.5 UX

[15] 3,681,964 [451 Aug. 8, 1972 3,427,847 2/ 1969 Harper ..72/326 X 3,435,654 4/1969 Papst ..29/163.5 X 2,320,651 6/1943 Poux ..72/ 196 X Primary Examiner-Milton S. Mehr Attorney-Gregory J. Nelson ABSTRACT shifting the material to a new position upon completion of a row of perforations.

10 Claims, 7 Drawing Figures 2| J 46 38 22 ll" 1 41 40 E IE I E;-

u u Ll s 1 u u u FIG.

INVENTOR DONALD J. DARLING ATTORNEY PATENTEBAUB 8 m2 SHEET 2 0F 2 FIG. 3

FIG. 2

I NVENTOR DONALD DARLING PERFORATING MACHINE AND METHOD This invention relates to a machine for perforating materials such as steel plate, pipe and other similar cylindrical objects with a row or multiple rows of regularly spaced perforations. More particularly, this invention relates to an apparatus for perforating steel pipe to form well screen.

Well screen and similar perforated tubes that permit passage of liquids or air therethrough have, in the past, been formed in a number of ways in order to achieve the desired number, configuration and size perforations to provide acceptable performance. Optimum well screen provides a large open area in relation to the surface area of the casing comprised of numerous perforations. For this reason, it is known to form wire wound screen which is simply a series of hoops spaced-apart by interior stringers which are welded or otherwise mechanically fixed to each hoop. Obviously, the cost of such construction can be prohibitive. To reduce the expense of well screen, it is also known to punch a series of rows of holes in steel sheet and thereafter roll the sheet into the desired cylindrical shape. In the prior art, it is also known to sequentially punch the desired perforation in the pipe exterior with a reciprocating punch. It has also been suggested to internally perforate pipe by insertion of various types of cutting members through the interior of the pipe. The former methods have proven to be very expensive and laborious, while the latter method has been limited to lighter gauge materials and is not adaptable to heavier gauge materials such as steel plate. Neither do these prior art methods of making well screens lend themselves to automatic and efiicient methods of manufacture.

' My invention overcomes the shortcomings of the prior art in that I provide means and structure for perforating cylindrical steel pipe of substantial thickness from the interior by hydraulically moving a cutting and forming head longitudinally through the pipe length. The cutting head is rotatable and provided with teeth which register with a female die positioned on the opposite side of the material as the perforations are made. The pipe is held in place during one reciprocating of the cutting head and then rotated a few degrees relative to the die and cutting head, so the operation can be repeated and another row of perforations formed.

It is then a primary object to provide an apparatus and method for automatically perforating-plate, pipe tubing with rows of perforations with a minimum expenditure of energy.

It is another important object of the present invention to provide a rotating cutting member that registers with a die to cut and form a regular row of perforation, each perforation having a shield formed by the cutaway metal, thereby providing an optimum perforation for well casing and the like.

Another object of my invention is to provide the means and structure for manufacturing well casing from ordinary steel pipe.

Another object of the present invention is to provide an efficient rotary cutting and forming tool having a mating female die and adapted to perforate pipe and similar objects as it is moved through or along the object to be perforated.

Another object of the present invention is to provide an apparatus that will form perforated well screen having an optimum configuration; that is, maximum permissible area of openings in relationship to the pipe surface area.

Still another object of the present invention is to provide a pipe perforating apparatus in which a rotary cutting tool is hydraulically reciprocated longitudinally through pipe to effect maximum efi'rciency.

Another important object of this invention is to provide a method of longitudinally perforating material with a moving cutter that registers with a mating die to cut and form the desired perforations.

I A still further object of the present invention is to provide an efficient pipe perforating machine and method adaptable to varying diameters and thickness of pipe. I

Other objects and features of my invention will become apparent. when the following description is read in connection with the accompanying drawings, in which:

FIG. 1 is a partial side elevational view, partly broken away, of the machine of the machine of the present invention with a steel pipe in place and the cutter retracted;

FIG. 2 is an end view of the machine of FIG. 1;

FIG. 3 is a detail enlarged end view of a part of FIG. 2 showing the cutting head and mating die;

FIG. 4 is an enlarged side view, partly broken away, showing the cutting head in a perforating position;

FIGS. 5 and 6 are enlarged detail views of the mechanism for rotating the pipe; and

FIG. 7 is an enlarged detail view of a perforation cut and formed by the apparatus of the present invention.

DESCRIPTION Referring now to the drawings in which the same reference numerals indicate corresponding elements throughout the several views, numeral 1 designates my pipe perforating machine generally and includes a frame having a horizontal base member 2 shown as a platform mounted beam or channel midway from which extends upstanding load bearing leg 3. Extending parallel to the base member 2 and vertically spaced apart therefrom and supported on leg 3 is carriage member 5 also shown as a channel or beam. Spaced vertically above member 5 and parallel thereto is guide member 6 which is supported by upstanding side members 7 and 8 from base member 2. As best seen in FIG. 2, note that supports 7 and 8 are laterally spaced apart from carriage member 5 to permit insertion of a pipe around element 5. Carriage member 5 is of a depth and length so as to accommodate the size pipe being perforated. The frame members are joined together by welding or other conventional means.

A series of inwardly converging rollers 9 are longitudinally aligned directly below member 5. These rollers are affixed to lower frame 2 through the expediency of transverse plates and axles to assist in sliding the pipe over frame member 5 into a working position.

Additionally, transversely mounted on base member 2 subjacent carriage member 5 are biasing members 10 which serve to hold the pipe 13 securely in place during operation. Each biasing member 10 comprises a generally H shaped frame centered with respect to the vertical centerline of the machine. Vertical legs 11 are slidably received in pipes 12 which contain compression coil springs which serve to bias the cross bar 14 upwardly into firm contact with the lower edge of the pipe. The biasing member are retractable by placing sufficient tension on retraction cables 15 secured to cross bars 14 through actuation of hydraulic cylinder 16 which will be explained in detail hereafter.

A superjacent A frame 17 having arms 18 and 19 extends from either end of upper guide member 6 and is formed with the apex above the midpoint of member 6. A vertical adjusting member 20 extends between the apex to member 6 and can be vertically extended to prestress upper beam member 6 downwardly to compensate for deflections therein as the perforations are formed by the cutting head. Yoke 21 comprised of two parallel spaced apart plates 24 is pivotally secured to member 6 at shaft 22 and is held in a locked position to member 6 by locking pin 23. To position a pipe around member 6, pin 23 is removed and yoke 21 swung upwardly to permit insertion of the pipe along rollers 9.

Locking handles 38 extend through yoke 21 and through support member 3 and each are affixed to a cam, not shown. Movement of the cam upon rotation of handles 38 will cause upper member 6 to move vertically, thereby permitting the relative spacing members 5 and 6 to be varied to accommodate various material thickness.

The cutting member 25, which forms an essential part of my device, includes a circular head 26 mounted for rotation about shaft 27 in traverse block 28. Peripherally arranged about circular head 26 are teeth 29 which are shown as having a generally square .configuration but beveled at the comers. The number and size of teeth is variable depending upon the length and spacing of perforations desired; however, I have found the best results are achieved when the teeth are arranged so that the leading edge 30 of the cutting tooth just engages in a cutting position as the preceding tooth completes its perforation. This is shown in FIG. 4. For example, for perforating 12 inch diameter steel pipe, I have used six equally spaced teeth of inch depth on a 6% inch diameter roller with the corner bevels being approximately 30.

Cutting head block 28 is provided with a lower bearing edge 31 that slidably engages a track 33 provided on the upper surface of carriage member 5. Track 33 is shown as two parallel hardened steel rails spaced apart to accommodate the teeth of the cutting head as it rolls along. Suitable lubrication of the track is supplied from oil reservoir 32 also mounted on block 25. Also, as clearly seen in FIGS. 3 and 4, teeth 29, upon rotation, register with the female die or sleeve 35 extending along the lower edge of member 6 above the cutting head. The female die is longitudinally slotted at 36 to permit registry of the teeth and is of sufficient depth to receive the metal cut and formed by the teeth. Suitable die material, such as a high alloy hardened steel, is necessary for wear. This die or guide serves several important functions, as it supports the cutting and forming action of the cutting head as well as preventing undue lateral movement of the teeth. No positive drive, such as a rack and gear, is required to drive the cutting head as it travels in its own perforation as it traverses the interior of the pipe. The adjusting member 20 serves to keep the die in right engagement with the surface of the material being perforated.

The reciprocatory of the cutting head is controlled hydraulically or pneumatically. Accordingly, a hydraulic cylinder 40 of the double acting type is horizontally arranged on member 5 with the end of the rod 41 being fastened to cutting block 28 by appropriate means. When the piston rod 41 is retracted, cutting head 25 assumes a position on carriage member 5 near the inner end of member 6. The cylinder is extended in conventional manner by directing pressurized fluid to the head end of the cylinder by use of appropriate control valve 42 and retracted in a similar manner by pressurizing the rod end. To permit automatic operation, the spools of hydraulic control valves, not. seen, are electrically operated from solenoid valves which, in turn, are actuated by well-known relay contacts or limit switches located to be contacted by block 28 as it moves along member 5. Control panel 43 contains the hydraulic control valves, reservoir, electrical controls and other components of the electrical and hydraulic system. Since hydraulic and electrical systems of this general type are well known in the art, and since they form no part of my invention per se, greater detailed description thereof is not deemed necessary.

The mechanism for rotating the pipe is shown in FIG. 1 and in greater detail in FIGS. 5 and 6. The mechanism 45 for rotating the pipe comprises two hydraulic cylinders 46 angularly mounted upon beam 6 near either end. Each of the mechanisms are similarly constructed as follows: The ends of the cylinder rod 47 are fastened to arms 48 which are, in turn, affixed to eccentric 50. Extending downward from eccentric 50 is reciprocating arm 51. Pivotally attached to reciprocating arm 51 at stub shaft 49 is a ratchet arrangement including a rocker 52 which is secured to channel 6 through fixed arm 55 so that reciprocation of arm 51 causes rotation of rocker 52 about shaft 56. Dog 53 extends from the lower end rocker 52 and is positioned to engage and rotate the pipe. Arcuate guide 54 affixed to the lower end of arm 51 engages the periphery of the pipe and serves to force the pipe away from the die to permit rotation upon downward movement of arm 51. The operation of the rotational mechanism will be explained in greater detail below.

OPERATION To perforate a piece of pipe, the operation is as fol the pipe upwardly into place. At this point, rod 41 of main cylinder 40 is fully retracted and, to start perforation, the proper switch on the control panel 43 is depressed pressurizing the cylinder 40. As the cylinder extends, cutting head 25 moves along carriage member 5 causing rotation of circular head 26 and teeth 29 to make a row of longitudinal perforations in the pipe wall as it advances through the pipe. The female die or guide 35 receives the teeth to control the cutting and forming action. When the cylinder is extended at the end of the pipe, a limit switch is actuated to cause the rod to retract in the same row it has just cut further shaping and extruding the perforations to the desired shape. I have found that although the perforations can be adequately made in a single traverse through the pipe, a complete traverse and return results in a more uniform perforation giving the maximum size and efficient shape of opening as seen in detail in FIG. 4. When the main cylinder 40 is retracted, the pipe is ready for rotation so that another row can be cut. Cylinders 46 are simultaneously actuated extending rods '47 causing arm 51 to move downward through eccentric 50 and shaft 48. The downward movement of arms 51 rotates rocker 52 clockwise to advance guide 54 upwardly on the pipe and dog 51 into engagement with the metal extruded from the perforation. Cylinder 46 is then retracted which results in a counter-clockwise rotation of rocker 53 causing the pipe to-be rotated the desired distance. To permit easy rotation of the pipe, cylinder 16 is simultaneously actuated during the rotation sequence to relieve the bias on the pipe.

The configuration of the perforation resulting from use of my novel apparatus is also of particular importance. Referring to FIG. 7, it will be seen that the cutting and forming operation perforates a generally rectangular slot on opening 58. The material 57 removed from the slot is sheared at longitudinal edges and formed into a raised section 57 that I refer to as a shield. Vertical openings 56 are formed along either edge of the cut. The shield formed thereby is particularly beneficial in well casing as it prevents infiltration of gravel and sand to the interior of the casing. Obviously, different combinations of cutting head and teeth will result in different shapes of openings but all having the useful shielded design described herein.

It will be apparent that with my novel cutting machine and method, any size and spacing of perforations can be achieved easily. Further, an efficient and adequate opening can be obtained and, since the perforations are cut and extruded, no cut away material results.

Also, it should be noted that, although Ihave made specific reference to perforating cylindrical shapes, my invention is not so limited. For example, my unique reciprocating cutting and forming die construction can equally well serve to perforate fiat plate or sheet. In such case, the rotating mechanism can be eliminated or adapted to move the plate horizontally a predetermined distance rather than rotatively. Also, it will be equally obvious that the relative position of the cutting head and die can be reversed with the die traveling above or along the outside of the object to be perforated. In the case of pipe, the die could be therefore located within the interior of the pipe, and the cutting head arranged superadjacent to longitudinally reciprocate along the outer periphery.

EXAMPLE A machine built and tested according to the foregoing description was made to accommodate 12 inch diameter steel pipe of up to A inch wall thickness. The hydraulic ram was 4 inches in diameter and a working pressure of about 500 psi was developed when cutting, meaning an effective force of about 6,000 pounds was cutting action in the die reduces the shear forces.

required. The perforations were about 2 inches in length and one-fourth inch in width with the maximum depth of the opening being about one-eighth inch giving an effective area of opening of opening of about 15 percent more than comparable well casings. Further, with my machine, standard pipe can be used resulting in substantial savings. The effective size of pipe my machine can perforate is limited only by the depth of beam 5 around which the pipe is positioned, as the reaction force from the cutting operation causes deflection of this member which must be minimized by adequate beam depth.

From the foregoing, it will be obvious that, with my unique apparatus incorporating a rolling cutting head having a mating die, I have provided a novel and efficient perforation apparatus. Changes and modifications will be obvious to those skilled in the art and, to the extent that they do not depart from the spirit and scope of the claims, they are covered therein.

Having fully described the invention in such manner as to enable those skilled in the art to understand and practice same, I claim:

1. A machine for impressing a row of spaced apart perforations in a material; said machine comprising:

a. a frame including a frame member adapted to support said material during said perforating operation;

b. a guide member extending longitudinally and having a female die member coextensive with the length of the row of perforations to be made, said die adapted to engage the surface of said material;

c. a cutting head provided with cutting means for perforating said material, said cutting means adapted to register with said female die and being positioned against the other surface of said material; and

(1. means for advancing said cutting head along said guide member whereby said cutting means registers with said die thereby cutting and forming predetermined longitudinal perforations in said pipe as said cutting head advances.

2. The machine of claim 1 further provided with means for shifting said material to a new predetermined working position to permit additional parallel rows of perforations to be impressed in said material.

3. A machine adapted to impress a row of longitudinal spaced apart perforations in a cylinder, said machine comprising:

a. a frame including a frame member adapted to support said cylinder during said perforating operation;

b. a guide member extending longitudinally and having a female die coextensive with the length of the row of perforations to be made, said die adapted to engage one surface of said material;

. a cutting head provided with cutting means for perforating said material, said cutting means adapted to register with said die and being positioned adjacent the other surface of said material;

and

d. means for advancing said cutting head along said guide member whereby said cutting means registers with said die, thereby cutting and forming predetermined longitudinal perforations in said pipe as said cutting head advances.

4. The machine of claim 3 further including means for rotating said cylinder to a new predetermined working position to permit additional parallel rows of perforations to be made in said cylinder. I

5. A machine for providing a row of spaced apart perforations in a cylindrical pipe, said machine comprising:

a. a frame including a longitudinal frame member adapted to receive said pipe;

b. a guide member extending adjacent and parallel to said frame member including a female die coextensive with the length of the row of perforations to be made, said die adapted to longitudinally engage the outer periphery of said pipe;

c. means to urge said pipe into engagement with said die in a working position;

d. a cutting head provided with cutting means for perforating said pipe, said cutting means adapted to register with said female die and being positioned within said pipe; and

e. means for advancing said cutting head along said guide member whereby said cutting means registers with said die thereby cutting and forming predetermined longitudinal perforations in said pipe as said cutting head advances.

6. The machine of claim 5 further providedwith means for shifting said pipe to a new predetermined working position to permit additional parallel rows of perforations to be placed in said pipe.

7. The machine of claim 6 wherein said cutting means comprises a circular rotative member having spaced apart teeth extending from the periphery of said circular member and said means for advancing said cutting head comprises a fluid actuated cylinder.

8. A pipe perforating machine comprising:

a. a frame including a horizontal frame member for securing said pipe in place during operation, said frame member adapted to extend longitudinally through the interiorof said pipe in an operational position, said guide further having longitudinal track means thereon;

b. a guide member extending parallel and superadjacent said frame member and including a female die coextensive with the length of the row of perforations to be made, said die adapted to longitudinally engage the outer periphery of said pipe in a working position;

c. biasing means to urge said 'pipe into engagement with said die;

d. a cutting head movable along said track, said cutting head including a rotative cutting member having peripheral teeth, said teeth being in registry with said die; I

e. means for advancing said cutting head along said guide die whereby said cutting means registers with said die thereby cutting and forming predetermined longitudinal perforation in said pipe as said cutting head advances; and

f. means for rotating said pipe relative to the die to a new working position upon completion of a row of marriage figtli e' nf si'iil i 2 1% 2. 1? gage a previously formed perforation in said pipe upon reciprocation of said arm in one direction and to impart rotation to said pipe upon reciprocation of said arm in an opposite direction.

' 9. The machine of claim 8 wherein means are provided to prestress said guide member to allow for deflections therein during operation.

10. A method of impressing a row of spaced apart perforations in a material comprising: I

a. supporting said material in a stationary working position;

b. placing a stationary longitudinal female die against one surface of the material, the length of said female die being coextensive with the longitudinal length of the row of perforations to be impressed;

c. placing a rotative toothed cutting means adjacentthe other surface. of said material; and

d. advancing said cutting means along said other sur- 

1. A machine for impressing a row of spaced apart perforations in a material; said machine comprising: a. a frame including a frame member adapted to support said material during said perforating operation; b. a guide member extending longitudinally and having a female die member coextensive with the length of the row of perforations to be made, said die adapted to engage the surface of said material; c. a cutting head provided with cutting means for perforating said material, said cutting means adapted to register with said female die and being positioned against the other surface of said material; and d. means for advancing said cutting head along said guide member whereby said cutting means registers with said die thereby cutting and forming predetermined longiTudinal perforations in said pipe as said cutting head advances.
 2. The machine of claim 1 further provided with means for shifting said material to a new predetermined working position to permit additional parallel rows of perforations to be impressed in said material.
 3. A machine adapted to impress a row of longitudinal spaced apart perforations in a cylinder, said machine comprising: a. a frame including a frame member adapted to support said cylinder during said perforating operation; b. a guide member extending longitudinally and having a female die coextensive with the length of the row of perforations to be made, said die adapted to engage one surface of said material; c. a cutting head provided with cutting means for perforating said material, said cutting means adapted to register with said die and being positioned adjacent the other surface of said material; and d. means for advancing said cutting head along said guide member whereby said cutting means registers with said die, thereby cutting and forming predetermined longitudinal perforations in said pipe as said cutting head advances.
 4. The machine of claim 3 further including means for rotating said cylinder to a new predetermined working position to permit additional parallel rows of perforations to be made in said cylinder.
 5. A machine for providing a row of spaced apart perforations in a cylindrical pipe, said machine comprising: a. a frame including a longitudinal frame member adapted to receive said pipe; b. a guide member extending adjacent and parallel to said frame member including a female die coextensive with the length of the row of perforations to be made, said die adapted to longitudinally engage the outer periphery of said pipe; c. means to urge said pipe into engagement with said die in a working position; d. a cutting head provided with cutting means for perforating said pipe, said cutting means adapted to register with said female die and being positioned within said pipe; and e. means for advancing said cutting head along said guide member whereby said cutting means registers with said die thereby cutting and forming predetermined longitudinal perforations in said pipe as said cutting head advances.
 6. The machine of claim 5 further provided with means for shifting said pipe to a new predetermined working position to permit additional parallel rows of perforations to be placed in said pipe.
 7. The machine of claim 6 wherein said cutting means comprises a circular rotative member having spaced apart teeth extending from the periphery of said circular member and said means for advancing said cutting head comprises a fluid actuated cylinder.
 8. A pipe perforating machine comprising: a. a frame including a horizontal frame member for securing said pipe in place during operation, said frame member adapted to extend longitudinally through the interior of said pipe in an operational position, said guide further having longitudinal track means thereon; b. a guide member extending parallel and superadjacent said frame member and including a female die coextensive with the length of the row of perforations to be made, said die adapted to longitudinally engage the outer periphery of said pipe in a working position; c. biasing means to urge said pipe into engagement with said die; d. a cutting head movable along said track, said cutting head including a rotative cutting member having peripheral teeth, said teeth being in registry with said die; e. means for advancing said cutting head along said guide die whereby said cutting means registers with said die thereby cutting and forming predetermined longitudinal perforation in said pipe as said cutting head advances; and f. means for rotating said pipe relative to the die to a new working position upon completion of a row of perforations, said means including a reciprocable arm having a dog thereon, said dog adapted to engage a previously formed perforation in sAid pipe upon reciprocation of said arm in one direction and to impart rotation to said pipe upon reciprocation of said arm in an opposite direction.
 9. The machine of claim 8 wherein means are provided to prestress said guide member to allow for deflections therein during operation.
 10. A method of impressing a row of spaced apart perforations in a material comprising: a. supporting said material in a stationary working position; b. placing a stationary longitudinal female die against one surface of the material, the length of said female die being coextensive with the longitudinal length of the row of perforations to be impressed; c. placing a rotative toothed cutting means adjacent the other surface of said material; and d. advancing said cutting means along said other surface whereby said cutting means is caused to rotate in registry with said die thereby cutting and forming perforations in said material as said cutting head advances. 